Evaporator for refrigerating apparatus



Nov. 22, 1927.

S. OTTO ET AL EVAPORATOR FOR REFRIGERATING APPARATUS Original Filed Jan. 18, 19 3 sheets-Sheet 1 Nov. 22, 1927. 1,649,973

S. OTTO ET AL EVAPORATOR FOR REFRIGERATING APPARATUS Original Filed Jan. 18, 1925 3 $heets-sheet OOOO 5 I W 44. W I @51 Mbtovnmf 4 I .7

Nov. 22, 1927. 1,649,973

s. OTTO ET AL EVAPORATOR FOR REFRIGERATING APPARATUS Original Filed Jan. 18, 1923 s Sheets-Shee't s nomtou.

l atented Nov. '22, 1927.

UNITED STATES PATENT OFFICE.

STUART OTTO, OF WILTON, CONNECTICUT, AND JACK CARL TANK US, OF SORANTON,

PENNSYLVANIA,

AUTOMATIC REFRIGERATOR COMPANY, A CORPORATION OF DELAWARE.

EVAPORATOR FOR REFRIGERATING APIARATIJ'S.

This invention is an improvement in evaporators for liquefied refrigerant, and adapted for use in refrigerators, cooling chambers, or the like. The invention relates particularly to that type in which the evaporator serves as a receiver for the liquefied refrigerant, and is alternately filled during the 'liquefying of the gas under pressure, and then slowly emptied by' reduction of the pressure of the gas andf the resulting evaporation of the liquid to produce the desired cooling effect.

In refrigerating systems of the absorption type it sometimes happens, due to improper regulation, failure of condenser water. or other causes, that some of the absorber liquid which is far less volatile than the liquepasses through the condenser and collects in .the evaporator where it interferes with the proper and eflicient operation of the system.

One important feature of "our invention resides in the novel means employed for automatically effecting a withdrawl of liquid at inter als from the evaporator, and returning it to the absorber, so as to prevent the accumulation of liquid of a char acter which is not readily volatile in the evaporator.

In carrying a float within the evaporator and serving to operate a valve, whereby at the beginning of the cooling or. evaporating period, liquid will be drawn orator, whereas during the main portion of the cooling or evaporating period, only gas resultin from the evaporation will be withdrawn rom the evaporator.

This invention involves several features of construction and other advantages will be pointed out hereafter, or will be apparent from a consideration of the forms illustrated in the drawings. In these-drawings Fi 1 is a front elevation of a refrigerator showlng our improved evaporator serving as a central vertical partition therein.

Fig. 2 is an enlarged vertical section of the evaporator and in a plane at right angles to the plane of Fig. 1, said plane being indicated by the line 22 of Fig.

Fig. 3 is a section on the line 3-3 of Fig.

' 2, a portion of one of the trays being broken away.

through the evaporator, and in a out the invention, we provide from the bottom of the evaplication filed January 18, 1923, Serial No. 613,442. Renewed May 5, 1927.

ASSIGNORS, BY DIRECT AND MESNE ASSIGNMENTS, TO. ICELESS Fig. 4 is a sectional detail on the line 44 of Fig. 2, but on a larger scale.

Fig. 5 1s a front view of a refrigerator showing a different construction of evaporator.

Fig. 6 is a horizontal section on ,the line 6(i of Fig. 5. v i

Fig. 7 is a vertical section on a larger scale lane parallel to that of Fig. 5, said plane ing indicated by the line 7-7 of Fig. 8.

F1g. 8 is a section on the line 8-8 of Fig.

- Fig. is a front elevation of a refrigerator Fig. 10 is a larger view of the evaporator shown in'Fig. 9, certain of-the parts being taken in section on the line 10-10 of Fig.

11 and Fig. 11 is a section on the line 11-11 of Fig. 10. v

' Our improved evaporator is particularly adapted for use in that system in which a liquefiable gas is driven out of an absorbent liquid by heating of theliquid in a still, and

the gas passes under the pressure of the still, through a condenser where it is cooled to such a point that it liquefies under pressure. The liquefied gas is delivered to the evaporator. Upon the shutting off of the heat from the still and the cooling of the absorbent liquid therein, the liquefied gas in the evaporator is caused to evaporate and pa$ back into the liquid in-the still which now serves as anabsorber. The liquefied gasduring its evaporation in the evaporator, produces the desired cooling effect.

Although our improved device may be made of various sizes, and for use in refrige erators or, cooling chambers of many different forms, we have selected, for purposes of illustration, forms adapted for use in the household sizes of refrigerators.

In Fig. 1 there is illustrated a refrigerator in which the evaporator forms a central vertical partition between storage chambers 10 upon opposite sides thereof, and containing suitable shelves for the support of the articles. to be cooled. This form of evaporator as shown more particularly in Figs. 2, 3 and 4', lIIOllldBS, an upper tank or receiver 11, a

lower tank or recei er 12, and a plurality I of substantially vertical pipes 13 arranged freezing chamber 15 which is open at oneadapted to lead through the condenser to the scribed. From the upper end of the trap a in-substantially the same plane and extending from the upper to the lower receiver.

As shown, the lower receiver 12 has an annular space 14 with which at least some of the tubes communicate, and encircling a end. Within this freezing chamber 15 are placed one orn ore'trays 16 ada ted to recelve the water to be frozen. referably each tray is subdivided by a series of vertical partitions 17, so as to form a plurality of compartments whereby the water is frozen into small blocks adapted for table use, or

to put into ice pitchers or drinking glasses.

With the chambers 12 and 15 circular in form the freezing chamber 15 may have two of these trays 16, and'each may occupy approximately one quarter of the available space in the freezing. chamber, the two trays being of quarter-circular form in cross-section. 'The tra s may be provided with suit: able handles 1 wherebythey may be drawn .out when ice is desired, or it is necessary to refill them.

' As one important feature we provide the evaporator with means whereby'the return pipe from the evaporator maybe automatically connected with'the lower part of the receiver 12 at desired intervals to draw off liquid from the latter. ceiver has only a (single pipe connection 19 boiler absorber. This pipe connection or conduit leads to a trap 20 in which scale or solid particles passing through the pipes ma collect without danger of interfering wit the operation" of the valve hereinafter depassage 21 leads laterally and connects with a passage 22 opening into the upper side of the receiver 11. At the lower end of this passage there is a valve seat 23 anda verticallymovable valve 24. The valve is con-- nected to the arm or lever 25, one end of which is carries a' oat'27..

A pipe 28 leads upwardly from the lowermost portion of the evaporator, and connects with the passage 22 intermediate-of the ends of the latter. The valve 24 has astemportion 29 slidable in the passage 22, and sub stantially closing the latter except for a small passage 30 along-one side of the valve stem, and leading upwardly from the valve. The valve stem 29 has a second passage 31 lengthwise thereof, and this at its lower, end communicates with a port '32 in the side of the valve stem. .The port is so positioned that when the valve stem is'in raised position and in engagement'with' the seat 23, the port 32 will communicate with thepipe 28, but when the valve stem is lowered to normal position with thevalve away from the valve seat, 7

the port 32 will be closed by the side wall As shown the re-.

ivoted' at 26, and the other end thZ tube 22, as indicated in dotted lines in 1 a in the operation of our improved device the liquefied gas is delivered from the still and through the condenser'and enters the "10 evaporator through the pipe 19. The float is now in lowermost position, as shown in dotted lines in Fig. 2; When the'evaporator has been substantially filled with liquid the floatwill rise and close the valve 24 and open the port- 32. Any further liquid which is delivered may pass into the. evaporator through the pipe 28. As soon as the heat is shut off at the still and the absorbing actic-n begins, the resulting suction will be through the pipe 28 from the evaporator, and this will be assisted'by. thepressure on the liquid in the evaporator-caused by the collection of gas in the upper part of the chamber 11 and resulting from evaporation of the 35 liquid and the absorption of heat from the refrigerator. I The liquid'level in the evaporator. will rapidly lower until the float opens the valve .28. Thereafter the gas resulting from the. evaporation can escape directly through the passage 30, and the pipe 28 will cease to function. -This operation will continue until all or the desired amount of the liquefied gas has been evaporated, and the heat is againturned. on to the still to stop the absorbing and begin the'di'stilling action. It will be noted that duringeach operation of the apparatus a small quantity of the liquid will be withdrawn from the lowerthe pipe. 19, and theicondenser, to the a sorber. Thus the heavier and less volatile liquidv which settles at the bottom of the I evaporator, will each time be turned off and the accumulation of such non-volatile liquid in the avaporator will be prevented.

In the construction shown in Figs. '5 to S inclusive, there is shown a somewhat difi'er-' I ent arrangement or receivers andpipcs for the evaporator. The upper receiver 11 1s connected to 'a very much smaller lower receiver 12, and these two receivers or tanks and the connecting pipes 13 are adapted to lie against the back wall of the refri erator. The. lower receiver12 has a pair-o cylin; 1.15 drical concentric spaced walls 33 and 34 extending forwardly therefrom at one end, and forming an annular chamber 14*. communi-- cating with the main lower tank 12. Within the inner wall-34 is a freezing chamber15 for the trays 16. The pipe 28 leads from the,

lowermost portion of the lower receiver, and

receiver 12 bytwo sets of. pipes 13" and 13.

most portion and returned directly throu h 9 two receivers to each other.

The larger number of pipes is used because of the smaller length and the nearness of the In this con struction we have not illustrated any icemaking trays, but have shown the lower receiver 12 connected by a pipe 28 to the side of the pipe 22 and controlled by a valve similar to that previously described, but the details of which are not illustrated in this form.

Itwill of course be evident that there may be various'other forms and arrangements of the receivers and pipe connections within the spirit of our invention, and within'thc scope oft-he appended claims.

Having thus described our invention, what we claim as new anddesire to secure by, Letters Patent is:

1. An evaporator having a supply pipe for liquefied refrigerant, a branch pipe therefrom to the lowermost portion of the evaporator, a float within said evaporator,

and valve mechanism operated by said-float for controlling oneof said pipes.

2. An evaporatorhaving a supply pipe for liquefied refrigerant, a branch pipe therefrom to the lowermost portion of the evaporator, a float within said evaporator, and valve mechanism operated by said float for opening one of said pipes and closing the other when the liquid level in the evaporator reaches a predetermined point.

3. An evaporator having a supplypipe for liquefied refrigerant, a branch pipe therefrom to the lowermost portion of the evaporator, a float within said evaporator, and valve mechanism operated by said float for opening the branch pipe and closing the first mentioned pipe when the liquid level in the evaporator reaches a predetermined levelf 4. An evaporator having a supply pipe for liquefied refrigerant, a branch p1pe therefrom to the lowermost portion of the evaporator, a float within said evaporator,

and valve mechanism operated by said float for closing the first mentioned pipe when vthe liquid in the evaporator accumulates 'to a pre etermined elevation.

5. An evaporator having a conduit connected thereto and serving for the delivery of liquid refrigerant and for the return of gaseous refrigerant, a conduit leading from the lowermost portion of the evaporator, a valve for controlling the fiowr of liquid from the body of the evaporator throu h said last mentioned conduit, and a float or controlling said valve. i a

6. An evaporator for intermittently operating refrigerating apparatus of the absorption type, including a liquid chamber, a conduit for delivering liquid refrigerant thereto and withdrawing gaseous refrigerant therefrom, a conduit leading from the lower portion of the liquid chamber, means for establishing communication between said second -mentioned conduit and said first mentioned conduit, a valve for controlling the flow through said second mentioned conduit, and a float for operating said valve.

7 An evaporator for intermittently oper-..

ating refrigerating apparatus of the absorption type, including a liquid chamber, a conduit for del'vering liquid refrigerant thereto and wit drawing gaseous refrigerant therefrom, a conduit leading from the lower portion of the liquid chamber, means for establishing communication between said second mentioned conduit and said first mentioned conduit, a valve in said connection, and a float for opening said valve and most portion of said container, a float within said container, and means controlled by said float for establishing communication between said second mentioned conduit and said first mentioned conduit whereby liquid from the lowermost portion of said container is delivered through said second mentioned conduit to a point from which it may be sucked from the evaporator through said first mentioned conduit at the beginning of the absorption period, if the liquid level in said container be'above a predetermined point. 1

9. An evaporator for an intermittently o crating refrigerating apparatus of the a sorption type, inclu ing a container for liquefied refrigerant, a single conduit connected to the upper part thereof for delivering said liquefied refrigerant during the heating period and for withdrawing gaseous refrigerant during the absorbing period, a second conduit leading from the lowermost portion of said container, and means for establishing communication between said second mentioned conduit and said first mentioned conduit whereby liquid from the lowermost portion of said container is delivered through said second mentioned conduit to a point from which it may be sucked from the evaporator through said first mentioned conduit at the beginnin of the absorption period, if the liquid evel 10.- An eva rator for an intermittently operating refiiigeratin abso'r tion'type, inclu g a container for lique 'ed refrigerant, a single conduit connected to the upper art thereof for deliver- I ing said said lique ed refrigerant during the heating period and for withdrawing gaseous refrigerant during the absorbing period, a second conduit leading from the owerlnost portion of said conduit, and means responsive to varying condltions 1n sa'id containerfwhereby liquid is, delivered sucked directly from the lowermost portion of the chamber through, said second mentioned conduit to be sucked from the container through said first mentioned conduit, or gas may be from the upper portion of the chamber through said first mentioned conduit.

- 11. An evaporator for an intermittently.

operating refrigeratin apparatus of the a sorption type, inclu ing a container for apparatus of the.

liquefied refrigerant, a single conduit connected to the upper part thereof for delivering said liquefied refrigerant during the heating period and for withdrawing gaseous refrigerant during the absorbing period,

a second conduit leading from the lowermentioned conduit.

portion of the container through said first I Signed at Scranton in the county of Lackawanna and State of Pennsylvania this 15th day of January, 1923.

STUART/OTTO. JACK CARL JANKUS. 

